Fuel injection device for internal combustion engines



' Sept. 7; 1 7; L, L EL 2,092,685

FUEL INJECTION DEVICE FOR INTERNAL COMBUSTION ENGINES;

Filed April 6, 1934 I 3 Sheets"Sheet 1 Source of Fuel Under Pressure W ill/ Bing/he Manifold Se t. 7, 1937. L. L. VIEL 8 I FUEL INJECTION DEVICE FOR INTERNAL COMBUSTION ENGINES Filed April 6, 1934 3 Sheets-Sheet 2 F/a/n Fue/ Pump K. f as 65 v 5 f Ely 1e Manifb/J J A 69 6 m l L 7/ Fram Fuel Pump To Tfiroffle firm v 6 Im/en/w gm mngw gg,

L. L. VIEL Sept. 7, 1937.

FUEL INJECTION DEVICE FOR INTERNAL COMBUSTION ENGINES Filed April 6, 1954 5 Sheets-Sheet 5 To Engine x ifanifoll To Thraffle Arm M W I a 7 5 5 a 4 w a 3 L 5 n n 5 l .& d m 0 M e m 0, F. .m

from Fuel Pump Q Z vMi QQZI/ Patented Sept. 7, 1937 UNITED STATES PATENT orr cs FUEL INJECTION DEVICE FOR INTERNAL COMBUSTION ENGINES Application April 6. 1934, Serial No. 319,367

In France April I, 11933 10 Claims. (UL 12%119) My invention relates to fuel injecting devices for internal combustion engines and more especially engines provided with an intake pipe which 1 receives a fuel mixture from a carburetor including a throttle valve.

The chief object of my invention is to provide a device of this-type which is capable of injecting a supplementary amount of fuel'into the engine when the throttle valve is being opened so that the engine may pick up morereadily. My device also permits of injectingfuel into the intake manifold when the engine is being started.

The fuel injecting device according to my. invention comprises a chamber communicating with a space filled with liquid through an orifice of small section, said chamber having two movable walls. One of these walls is operatively con- The space filled with liquid which communicates with the chamber of the injecting device may consist of the very source of fuel under pressure from which the injecting device is fed. 30 Preferred embodiments of the present invention will be hereinafter described with reference to the accompanying drawings, given merely by way of example, and in which:

. Fig. l is an elevational view of an engine intake manifold provided with a carburetor and an injecting device according. to my invention;

Fig. 2 diagrammatically shows, in longitudinal section, the injecting device of Fig. 1;

Fig. 3 and Fig. 4 are diagrammatical views 40 showing in longitudinal section, injecting devices embodying diaphragms;

Fig. 5 diagrammatically shows, in longitudinal section, a modification of the device shown in' In the embodiment shown in Fig. 1, a carburetso or I is fitted on the intake manifold 2' of the en-.

gine. The amount of fuel mixture supplied by the carburetor is controlled by means of throttle valve 3 operated through arm 4. Fuel under pressure is fed to the carburetor through con- 65 duit 5. This conduit is preferably fed with fuel fed through, carburetor l.

by means of a pump. The injecting device 6 is fed with fuel through a conduit 7 connected to conduit 5. A conduit t connects the outlet of the injector t with a jet 9 opening into manifold. 2.

The details of the injecting device 5 are shown 5 in Fig. 2. In this figure, the numeral it represents a chamber communicating with a conduit 92 through an orifice of small section it. Conduit i2 is permanently connected with feed conduit l. Chamber M is also connected with pas- 10 sage it through an orifice it controlled by a check valve it through which fuel is prevented from flowing from conduit it into chamber it. Conduit it further communicates with a space iii in the wall of which is fitted a washer it. bored 15 in ltand pressed by a threaded plug lflii having an axial bore till. Space it communicates with the jet ii through bores it and 9M and conduit t. Jet t is providedat its end with a calibrated spindle it which projects from the casing of the injecting device by passing through a fluidtight 5 packing. 0n the outer portion of spindle 2i there is mounted a lever 22 connected, through a rod 23, to the arm t of the throttle valve (Fig. 1). A second piston 24 is slidably mounted in another cylindrical partiof chamber W. The end 25 of piston it constitutes a valve which, when applied against Washer 28, closes orifice iii. A. spring ii, compressed between piston 2t and a shoulder 2%, carried by the wall of chamber i0, tends to push this piston toward washer 26, to close orifice it.

A plug 29 makes it possible to remove the air that maybe contained in the apparatus.

The operation of the device takes place as follows: When throttle valve 3 and arm 6 are main- E tained in a given position, the engine is normally The port 16 of theinjecting device is closed by the end 25 of piston 26, which is applied against surface'26, and jet 9 does not supply fuel.

'parts when the throttle valve is opened. The dis-" placement of piston ll toward'the left as viewed in Fig. 2 produces a suction in chamber l0 but the cross section of orifice II is too small for permitting a volume of fuel equal to the volume gen- I erated by the displacement of piston l8 to flow in a short time through said orifice I i. The pressure in chamber l6 therefore drops and piston 24 is drawn in, compressing spring 21. Port I6 is then uncovered, and fuel fiows through conduit 1, conduit I2, orifice l6, conduit 6 and the orifice l1 through which this fuel is injected into the intake manifold 2. Spring 21 then pushes back piston 24, while fuel is entering chamber [8 through orifice The low rate of flow through orifice retards the return stroke of piston 24. Injection stops as soon as the end 25 of piston 24 comes back into contact with surface 26. The rate of fiow of the injecting device is adjusted by varying the section of calibrated orifice l1, while the time for which injection takes place depends on the strength of spring 21 and the area of orifice In Fig. 2, I have shown the various parts in the positions they occupy after the throttle valve has been opened, before the end of the injection.

When the throttle valve is' suddenly closed, movement is again transmitted to piston 18, which tends to drive out the fuel contained in chamber in. The low rate of flow through orifice does not permit, by itself, a quick displacement of piston l8, but the increase of pressure created in this chamber lifts valve |4, so that fuel is evacuated simultaneously through orifice II and the orifice of large section i3. If orifice l3 did not exist, the rate of fiow through orifice would be too small to permit the quick displacement of piston I8 .as the throttle valve is being closed, and this movement would be retarded.

The device above described is very efiicient. On the one hand, while the engine is accelerating the calibrated orifice I1 is fed under the pressure of the fuel pump, which ensures a good spraying of the fuel despite the fact that the suction in pipe 2 at this time is very small. On the other hand, jet 9 opens into the intakemanifold of the engine behind throttle valve 3 and preferably as close as possible to the inlet valves. With such an arrangement, the injected fuel goes directly to the inlet valves, without having had time to deposit on the walls of the manifold. The fact that the supplementary fuel fed while the engine is accelerating is discharged into the intake manifold behind the throttle valve is an essential feature of the present invention, and this arrangement constitutes an important featurewhatever be the nature of the device that is utilized for the injection of supplementary fuel.

Pistons l8 and 24 can obviously be replaced by diaphragms, as shown in Fig. 3. In this figure, a chamber 36 communicates with a second chamber 3| through an orifice of small cross section 32 and a second orifice 33 provided with a check valve 34. Chamber 3| is connected, on the one hand through conduit 35, with the fuel pump or any other source of fuel under pressure, and, on the other hand, through an orifice 36, controlled by a valve 31, with a conduit 36 leading to a discharge jet, such as jet 9 in Fig. 1. Chamber 3D is closed by two diaphragms 39 and 40. Diaphragm 39 is connected, through a rod 4|, with a lever 42 pivoting about an axis 43. Lever 42 is itself connected, through a rod 44, with'the throttle valve control arm. Diaphragm 40, which separates chamber 30 from chamber 3|, is connected to valve 31 for instance through a small rod as shown in the drawings. A spring 45 tends to bring diaphragm 40 back into the position wherein the valve 31 is closed.

'49 controlled by a check valve 50.

53. Injection takes place.

The operation of the device is exactly the same as that above described with reference to Fig. 2, diaphragm 39 playing the same part as piston I8; diaphragm 46 playing the same part as piston 24; valve 31 playing the same part as the end 25 of piston 24; and orifice 32 playing the same part as orifice H in the preceding example.

In the embodiment of Fig. 4, a chamber 46 communicates with a second chamber 41 through an orifice of small cross section 48 and an orifice Chamber 41 is connected, on the one hand through a conduit 5|, with the fuel pump or any other source of fuel under pressure, and, on the other hand through an orifice 52 controlled by a check valve 53, with a conduit 54 leading to a jet such as jet 9 of Fig. 1. Chamber 46 is closed by two diaphragms 55 and 56. Diaphragm 55 is connected, through a rod 51, with a lever 58 pivoting about axis 59. Lever 58 is itself connected, through a rod 60, with the throttle valve control arm. Diaphragm 56, which separates chamber 46 from second chamber 41, is connected to valve 53 for instance through a small rod as shown in the drawings and is subjected to the action of a spring 6| which tends to maintain valve 53 in the closed position.

This device operates in the following manner:

- Under normal conditions, valve 53 is closed, and

the device does not feed fuel to the engine through conduit 54. When the engine is to accelerate, the throttle valve control -arm drives rod 60, lever 58 and rod 51 in the directions indicated by the arrows. Diaphragm 55, displaced by rod 51, exerts pressure on the fuel contained in chamber 46. The pressure developed in this chamber forces valve 50 against its seat and the area of orifice 48 is too small to permit a sufficient rate of fiow ofthe fuel driven out by diaphragm 55 through sald'orifice. Diaphragm 56 is therefore pushed toward the left as viewed in Fig. 4, compressing spring 6| and opening valve Spring 6| gradually brings back diaphragm 56- into its initial position, driving out fuel from chamber 46 through orifice 48. Injection ceases when valve member 53 returns to its seat. In the case of a sudden closing of the throttle valve, check valve 50 is lifted from its seat-and permits of chamber 46 being filled through the orifice of larger section 49.

In the devices that have been above described use is made of the fuel itself for filling the chamber provided with movable walls. In Fig. .5 I have shown a modification of the device shown in Fig. 2 in which use is made of an independent liquid for filling this chamber. This device comprises a cylindrical chamber 62in which are fitted two pistons 63 and 64. Piston 63 is operated, through a rod 65 and a lever 66, by a shaft 61 operatively connected to the. throttle valve. The

throttle valve is, thus operatively coupled with piston 63, in the same manner as it is coupled with piston I8 in the modification of Fig. 2.

fluid whatever.

Under normal conditions of working,'piston 8t maintains valve member 89 applied against its the device.

ment of the movable wall that carries the valve seat, provided however that the pressure of the liquid that fills chamber 82 is higher than'tlie pressure of the fuel present in conduit II. The injecting device does not work. when 'the throttle valve is opened, piston 63 moves in the takes place as piston 64 draws valve member 69 along with it and opens orifice 69. Piston 69 is then brought back into its initial position bythe pressure of the liquid contained in chamber 62 as the liquid is penetrating into this chamber through orifice l3.

In case of a sudden closing oi." the throttle valve, the liquid driven out by piston 63 is evacuated through orifice i l by lifting check valve member 15 from its seat.

The liquid under pressure that fills chamber 62 may consist of lubricating oil under pressure from the engine. It sufiices to connect conduit 82 with any point of the lubricating circuit. Th use of lubricating oil has the advantage of lubricating pistons 63 and 64 and of eliminating sticking .of these pistons in cylinder 62, as may happen when the pistons are immersed in gasoline.

This modification is illustrated by Fig. 5a showing the engine 2, the whole accelerating device of Fig. 5 pointed out as I03, the fuel pump tilt,

feeding fuel to the carburetor I05 and to the accelerating device I03, the lubricating pump It, and the conduit I2 connected to the outlet pipe in! of lubricating pump W8.

The presence of air or gas bubbles in the chamber provided with movable walls as above described is detrimental to the proper working of As a matter of fact, the displaceby which the flow of fuel is controlled immediately follows the movements of the movable wall mechanically actuated by the throttle only if the The device comprises five compartments: 19, II, ll, l9, l0. Compartments i9 and I! are separated from each other by a deionnable, diaphragm 8i. Compartments It and I8 are separated 'i'rom each other by a deformable diaphragm 92. CompartnYent is closed by a dei'ormable diaphragm 93. Compartment it is connected withthe inlet iuel conduit 34 and with the outlet fuel conduit "which communicates with the englne'intake pipe. The connection be-- [direction shown by the arrow; creating a suction .that is transmitted to piston 64. Fuel injection chamber closed by these two movable walls con-- tains a practically lnexpansible liquid.- If'this chamber contalns'air or gas bubbles, these air bubbles have a tendency to expand when one of these walls is actuated by the throttle in the direction that increases the volume-of this chamber, and the displacement of the other wall is thus reduced and can even become zero if the quantity of gas contained in the chamber is sufliciently great, which prevents the device from working in a satisfactory manner. On the contrary, when the chamber contains a liquid entirely free from gases, the displacements oi the-twomovable walls correspond to strictly equal volumes, which ensures a uniform and reliable working of the apparatus.

In order to avoid the eventual presence of gases or vapors in the chamber of the apparatus, in a modification shown by Fig. 6 the space with which said chamber is connected is closed by a movable wall, the whole of said chamber and said space constituting an entirely closed volume; This volume is initially filled with a liquid which is preferably little volatile, then it is thoroughly freed from any air or gases that it may contain, after which it is definitely closed. In this manner, the presence of gases or vapors inside the chamber is obviously avoided.

This arrangement is shown in Fig. 6:

which is a little volatile and the tween compartment it and the outletv conduit Bliis controlled by-a valve member 09 fixed to diaphragm M. Compartment II is further connected to compartmentla through a passage '81. A spring 88 disposed between diaphragm ti and wall 89 which separates compartments "and Ti from each other, tends to push diaphragm 8i toward the 'right hand side close valve member 86. Compartment ll communicates with compartment 89 through a rela tively large conduit Qt, and'these two compartments communicate with icompartment lil through an orifice of small section 9|. Compartments l9 and B0 are further interconnected through a conduit 32 controlled .by a check valve member 93, which permits the free passage of liquid from compartment 90 toward compartment I9, but which prevents liquid from flowing in the opposite direction. A lever 94 mounted on an axis 95 and operatively connected to the engine throttle valve carries a heel member 98. A spring 9t, interposed between the wall 98 that separates the two compartments l9 and Ill from each other and diaphragm 83, tends to maintain this diaphragm applied against heel member 96. Spring 91 is stronger than spring.

. The whole of compartments 80 and 'llconstitutes what has been called in connection with the previous modification the first chamber of the device, whiie compartment 19 constitutes what has been called the second chamber communicating with this first chamber through the orifice of small sectiont l. The filling of the chamber takes place by removing plug 99 which is located at the top of chamber "-47! so as to permit of easily freeing chamber "-11 and compartment 19 from the air and the gases that they may vcontain.

of the figure and to Once chamber ll-30 has been filled with a liquidgases have been driven out, the chamber and the space are definitively closed by replacing plug 99.

The operation of this device is the following: I

When the throttle valve is opened, lever 91, which is mechanically connected with the throttle valve, is actuated in the direction of arrow I90.

Heel member moves away from diaphragm 83,

but spring 91 pushes the diaphragm until it is brought back into contact with heel member 96. This displacement of diaphragm 89, which produces an increase in the volume of compartment 80, draws in through conduit 90 the liquid contained in compartment 11 and, therefore, to draw in membrane Bl while compressing spring 88. This displacementof diaphragm BI causes valve member 86 to be moved to open position. The outlet conduit 85 then is in free communication with conduit 84 which is fed with fuel under pressure, so that the device injects fuel under pressure into the intake manifold of the engine.

Spring Bil slowly pushes back diaphragm 9| as the liquid contained in compartment 19 is flowing into compartment 11 through the orifice of small section 9| and conduit 90, thus permitting the volume of chamber ll-801m increase, as a result tion of spring 88. The flow of liquid from compartment 18 toward chamber 11-88 is accompanied by a displacement of diaphragm 82 which is subjected, on its face which forms one end of compartment 18, to the fuel feed pressure, since compartment 18 communicates through conduit 81 withfuel feed conduit 84.

With the arrangement shown in the drawings, the period of time for which injection takes place is independent of the fuel feed pressure. In fact, diaphragm 82 is subjected to no stress and there exists in compartment I8, and also in compartment 18, a pressure equal to the pressure in compartment 16, that is to say to the fuel feed pressure. The difference of pressure existing between compartments l6 and TI corresponds to the thrust exerted by spring 88 and is distributed over,the surface of diaphragm 8 I. This difference of pressure is independent of the fuel feed pressure. As the pressure in compartment 18 is always equal to the pressure in compartment 16, the difference between the pressures that exist in compartment 18 and in compartment 11 is equal to the difference-between the pressures in compartments Ti and I5 respectively, and it is therefore independent of the fuel feed pressure. As the rate of flow through orifice 8|, and consequently the time during which injection takes place, depend upon this difference of pressure, it is clear that the time during which injection takes place does "not depend upon the fuel feed pressure.

The operation of the device shown in Fig. 6 is the following:-

when the engine throttle valve is closed, lever 84 is actuated in the direction opposed to that indicated by arrow I00. The liquid driven by the corresponding displacement of diaphragm 83 penetrates into compartment 19, lifting valve member 83 from its seat and pushing back diaphragm 82, which itself drives out the fuel con-' tained in compartment 18, which is freely connected with the fuel feed conduit 84. The only resistance opposed to this movement is due to the fuel feed pressure that is transmitted to diaphragm 82,

In all the devices that have been above described, I provide a discharge orifice controlled by a check valve and permitting a quick return stroke of the movable wall (piston or diaphragm) connected to the throttle valve, when the latter is being closed. Obviously this discharge orifice can be dispensed with, while permitting a quick return of the throttle valve to the closed position, by controlling the displacements of the movable wall through the throttle valve only in the direction of opening as shown in Fig. '1. Under these conditions, movable wall is driven through cam 51* when the throttle valve is being opened, but, when said throttle valve is suddenly closed, said movable wall 55 does not follow the movement of said cam 51 and comes back slowly into contact therewith, whatever be the speedwith which the throttle valve has been closed.

The device according to my invention can be utilized not only as a fuel injecting device when the engine is'accelerating, but also as a fuel in- -jecting device for the starting of the engine. It

suffices, for thispurpose, to operate either the throttle arm, or directly the arm of the injecting '"-*started,.provided, however, that the fuel conduit is under pressure. v

Preferably, above mentioned dlaphragms consist of a flexible material such as a fabric treated in any suitable manner in order to make it fluidtight. Such diaphragms undergo deformation without opposing any material elastic reaction.

While I have disclosed in the preceding description, what I deem to be practical and eflicient embodiments of my invention, it should be well understood that I do not wish to be limited thereto as there might be changes made in the arrangement, disposition, and form of the parts without departing from the principle of my invention as comprehended within the scope of the appended claims.

liquid, a second chamber filled with the same liquid, a channel of restricted section of flow connecting these two chambers with each other, said first mentioned chamber having two movable walls, means for actuating one of these walls, and valve means in said passage 'operatively connected with the second movable wall for controlling the communication between said source of fuel and said conduit, said source of fuel being adapted to feed said fuel outlet under super-atmospheric pressure as said valve means are open.

2. An accelerating device for an internal combustion engine, which comprises, in combination, a source of fuel under pressure, a conduit, said conduit having a fuel outlet for feeding fuel to said engine, a passage between said source of fuel and said conduit, a first chamber filled with a liquid, 9. second chamber filled with the same liquid, a channel of restricted section of flow connecting these two chambers with each other, said first mentioned chamber having two movable walls, means for actuating one of these walls, elastic means for urging the other movable wall in one direction, valve ,means in said passage, operati ely connected with said second mentioned wall, for controlling the communication between the source of fuel and the conduit in such manner as to normally stop this communication when said second mentioned wall is subjected merely to the action of said elastic means and to open this communication when said second mentioned wall is moved against the action of said elastic means in consequence of a corresponding movement imparted to the first mentioned movable wall, said source of fuel being adapted to feed said fuel outlet under superfuel and said conduit, a first chamber filled with a liquid, a second chamber filled with the same liquid,a channel of restricted section of fiow connecting these two chambers with each other, said first mentioned chamber having two movable walls, means for actuating one of these walls in either of two opposite directions with respect to said first mentioned chamber, elastic means for urging the other movable wall inone direction, valve means in said passage, operatively connected to said second mentioned movable wall,

this communication when said second mentioned wall is moved against the action of said elastic means in consequence of a corresponding movement imparted to the first mentioned movable wall, a channel of relatively large section between said chambers, and a check valve in said last mentioned channel adapted to prevent the fiow of liquid through said last mentioned channel in a direction corresponding to a displacement of said second mentioned wall under the action of said elastic means while the first mentioned wall is stationary, said source of fuel being adapted to feed said fuel outlet under super-atmospheric pressure as said valve means are open.

4. An accelerating device for an internal combustion engine, which comprises, in combination, a source of fuel under pressure, a conduit,,said conduit having a fuel outlet for feeding fuel to said engine, a passage between said source of fuel and said conduit, a first chamber filled with a liquid, a second chamber filled with the same liquid, a channel of restricted section of flow connecting these two chambers with each other, said first mentioned chamber having two movable walls, means for actuating one of these walls in either of two opposite directions with respect to said first mentioned chamber, elastic means for, for urging the other movable wall outwardly with respect tosaid first mentioned chamber, valve means in said passage, operatively connected with said second mentioned movable wall, for controlling the communication between said source of fuel and said conduit in such manner as normally to stop this communication when said second mentioned wall is subjected only to the action of said elastic means, and to open this com- .munication when said second mentionedwall is moved inwardly against the action of said elastic means in consequence of an outward displacebetween these two chambers, and a check valve in said last mentioned channel adapted to prevent liquid from flowing through said last mentioned channel from the second mentioned chamber into the first mentioned chamber, said source of fuel being adapted to feed said vfuel outlet under super-atmospheric pressure as said'valve means are open.

5. An accelerating device for an internal combustion engine, which comprises,,in combination, a source of fuel under pressure, a conduit, said conduit having a fuel outlet for feeding fuel to said engine, a passage between this source of fuel and this conduit, a first chamber filled with a liquid, .a second chamber filled with the same liquid, a. channel of restricted section of fiow connecting these two chambers with each other, said first mentioned chamber having two movable walls, means for actuating'one of these walls in either of two opposite directions with respect to said first mentioned chamber, elastic means for urging the other. movable wall inwardly with respect to said first mentioned chamber, valve means in said passage operatively connected with said second mentioned movable wall for control lingthe communication between said source of fuel and said conduit in such manner as to normally stopthis communication when-said second mentioned wall is subjected only to the action of said elastic means and to open this communication when said second mentioned movable wall is moved outwardly against the action of said elastic means in consequence of an inward movement imparted to the first mentioned movable wall, a channel of relatively large section of flow between these two chambers, and a check valve in said last mentioned channel adapted to prevent liquid from flowing through said last mentioned channel from the first mentioned chamber into the second mentioned chamber, said source of fuel being adapted to feed said fuel outlet under super-atmospheric pressure as said valve means are open.

6. An accelerating device for an internal combustion engine, which comprises, in combination, a source of fuel under pressure, a conduit, said conduit having a fuel outlet for feeding fuel to said engine, a passage between said source of fuel and said conduit, a first chamber filled with Y a liquid, a second chamber filled with the same liquid, a channel of restricted section of fiow connecting these two chambers with each other, said first mentioned chamber having two movable walls, means for actuating one of these walls in only one direction, elastic means for urging the other movable wall in one direction, and valve means in said passage, operative by said secondmentioned movable wall, for controlling the communication between said source of fuel and said conduit in such manner as to normally stop this communication when said second mentioned wall is subjected merely to the action of said elastic means and to open this communication when said second mentioned wall is moved against the action of saidelastic means in consequence of a movement imparted to the first mentioned wall through said first mentioned means, said source of fuel being adapted tofeed said fuel outlet under super-atmospheric pres sure as said valve means are open.

7. An accelerating device for an internal combustion engine, which comprises, in combination, a source of 'fuel under pressure, a conduit, said conduit having a fuel outlet for feeding fuel to said engine, a first chamber. filled with said fuel,

a second chamber communicating with said source of fuel, a channel of restricted section of flow connecting these two chambers with each other, said first mentioned chamber having two movable walls, means for actuating one of these walls, a passage between said second mentioned chamber and said conduit, and valve means in said passage, operatively connected with the other movable wall, for controlling the communication between said second mentioned chamber .and said conduit, said source of fuel being adapted to feed said fuel outlet under super-atmose pheric pressure as said valve means are open.

8. An accelerating device for an internal combustion engine, which comprises, in combination, a source of fuel under pressure, a conduit, said conduit having a fuel outlet for feeding fuel to' said engine, a passage between said a source of fuel and said conduit, a first chamber filled with a liquid distinct from said fuel, a second chamber filled with the same liquid, a channel of restricted section of flow connecting these two chambers with each other, the whole of these two chambers having no connection whatever with said source of fuel, said conduit and said passage, said first mentioned chamber having two movable walls, means for actuating one of these walls, and .valve means in said passage, operatively connected with the other movable wall, for controlling the communication between said source of fuel and said conduit, said source of fuel being adapted to feed said fuel outlet under super-atmospheric pressure as said valve means are open.

9. An accelerating device for an internal combustion engine, which comprises, in combination, a source of fuel under pressure, a conduit, said conduit having a fuel outlet for feeding fuel to said engine, a passage between said source of fuel and said conduit, a first chamber filled with a non-volatile liquid, a second chamber, of variable volume, fllled with the same liquid, a channel of restricted section of flow connecting these two chambers with each other, the whole of these two chambers being entirely closed and without communication with the outside, said first mentioned chamber having two movable walls, means for actuating one of these walls, and valve means in said passage, operatively connected with the other movable wall, for controlling the communication between said source of fuel and said conduit, said source of fuel being adapted to feed said fuel outlet under superatmospheric pressure as said valve means are open.

10.- An accelerating device for an internal combustion engine, which comprises, in combination, a source of fuel under pressure, a conduit, said conduit having a fuel outlet for feeding fuel to said engine, a passage between said source of fuel and said chamber, a first chamber filled with a non-volatile liquid, a second chamber filled with the same liquid, a movable wall to said second mentioned chamber, a channel of restricted section of flow connecting these two chambers with each other, the whole of these two'chambers being entirely closed and without communication with the outside, said first mentioned chamber having two movable walls, means for actuating one of these two last mentioned movable walls, valve means in said passage operatively connected with the other of these two last mentioned movable walls for controlling the communication between said source of fuel and said conduit, and a chamber communicating with said passage and one wall of which consists of the movable wall of the second mentioned chamber, said source of fuel being adapted to feed said fuel outlet under superatmospheric pressure as said valve means are open.

LOUIS LEON VIEL. 

